Help - save underexposed images on Ilford FP4+

I have some severely under exposed negs that I haven't processed yet. FP4+ (125) mistakenly metered at ISO 3200. The situation was in full sun and quite contrasty. Metering is likely to be a good average but 4.5 stops under exposed. Any suggestions on chemicals/timing for extracting the best I could from these or is there really no hope???

The images are of a good friend of mine in intimate conversation with Elliot Erwitt (yes from Magnum) yesterday and would have huge sentimental value for her. I would be v greatfull for any suggestions.

ilford recommends 16 min in Microphen

If the negs are important (as it sounds they are) shoot some more at the same asa in similar light and then cut the film into sections and experiment. You are seriously into N- devlopment here so you will expect low contrast, so look for a developer that increases contrast (trying to think of one at the moment but brain is tired.) once you have something that works, then develop the important roll. Good luck.

The Film Developing Cookbook has some recipes for latent image intensification that uses hydrogen peroxide vapor to treat the film after development. It supposedly will increase the true speed two or three stops. Apparently this really does work to add speed to the film and is used by astronomers to maximize film speed. i can look up the specifics if you do not have access to the book.

john - take an example from the zone system...
ilford says that fp4 records -1.5 stops more of the low values. that is true by my expiriance (but a very good lenses are very important here, and then those values will be usable). so u actually start from here. now the development...
first of all - it should be or rodinal or pmk-pyro(which will help u more to make the low values usable).
on rodinal u should reduce the development by 25% at least. then put it for short time in selenium to make it more crisp (but not too much time since the high values will go too far).
all this will bring your zone 9 to about the zone 5/6 and the zone 5 to about zone 3. and if the exposures where "good" and the lenses were good u will have the extra 1.5 stop in the low values (vissible beyond the negative base).
printing:
grade five on condenser head and the ilford mg paper. expose the paper to about the full black (or one step higher) and see if the contrast is good enough. if not than the high contrast developer for paper is recomended (u know the fotospeed two bath developer, so u can use only that with the high grade).
than of course the deluted selenium (1+19) for about 5-10 min.
other option is lith print if that what u want.
any way - the idea is to make a low contrast negative, which will be printed on very high contrast way.
the print cannot be enlarged big of course because u will loose contrast in higher magnification.

A company called Speedibrews in the UK produce a developer called Cellar Stella that may just do the job. Michael Maunder, the owner does a lot of astronomy photographs and regularly rates FP4 at 1000+ ISO. It may be worth having a look on the net to find him.

www.speedibrews.co.uk, or buy at www.silverprint.co.uk

Thanks all for taking the time .... we'll see what happens. If they're any good I'll post the results.